What are the potential pitfalls of relying on global evaluation of superglobal variables in PHP development?

Potential pitfalls of relying on global evaluation of superglobal variables in PHP development include security vulnerabilities such as injection attacks and unintended variable modification. To mitigate these risks, it is recommended to explicitly access superglobal variables within functions or methods rather than relying on global evaluation.

// Example of accessing superglobal within a function
function getPostData() {
    if(isset($_POST['data'])) {
        return $_POST['data'];
    } else {
        return false;
    }
}